Woe unto them that are wise in their own eyes. The fifth woe. Self-conceit is the antithesis of humility; and as humility is, in a certain sense, the crowning virtue, so self-conceit is a sort of finishing touch put to vice.
While a man thinks humbly of himself, there is a chance that he may repent and amend. When he is "wise in his own eyes," he does not see why he should change.